#coding=utf-8

#代码修改自wangfei(wangfei@hanwang.com.cn)的C++代码
#参见：http://download.csdn.net/source/1178

#******************************************************************************
# 下面为阴历计算所需的数据,为节省存储空间,所以采用下面比较变态的存储方法.
#******************************************************************************
#数组g_lunar_month_day存入阴历1901年到2050年每年中的月天数信息，
#阴历每月只能是29或30天，一年用12（或13）个二进制位表示，对应位为1表30天，否则为29天
g_lunar_month_day = [
    0x4ae0, 0xa570, 0x5268, 0xd260, 0xd950, 0x6aa8, 0x56a0, 0x9ad0, 0x4ae8, 0x4ae0,   #1910
    0xa4d8, 0xa4d0, 0xd250, 0xd548, 0xb550, 0x56a0, 0x96d0, 0x95b0, 0x49b8, 0x49b0,   #1920
    0xa4b0, 0xb258, 0x6a50, 0x6d40, 0xada8, 0x2b60, 0x9570, 0x4978, 0x4970, 0x64b0,   #1930
    0xd4a0, 0xea50, 0x6d48, 0x5ad0, 0x2b60, 0x9370, 0x92e0, 0xc968, 0xc950, 0xd4a0,   #1940
    0xda50, 0xb550, 0x56a0, 0xaad8, 0x25d0, 0x92d0, 0xc958, 0xa950, 0xb4a8, 0x6ca0,   #1950
    0xb550, 0x55a8, 0x4da0, 0xa5b0, 0x52b8, 0x52b0, 0xa950, 0xe950, 0x6aa0, 0xad50,   #1960
    0xab50, 0x4b60, 0xa570, 0xa570, 0x5260, 0xe930, 0xd950, 0x5aa8, 0x56a0, 0x96d0,   #1970
    0x4ae8, 0x4ad0, 0xa4d0, 0xd268, 0xd250, 0xd528, 0xb540, 0xb6a0, 0x96d0, 0x95b0,   #1980
    0x49b0, 0xa4b8, 0xa4b0, 0xb258, 0x6a50, 0x6d40, 0xada0, 0xab60, 0x9370, 0x4978,   #1990
    0x4970, 0x64b0, 0x6a50, 0xea50, 0x6b28, 0x5ac0, 0xab60, 0x9368, 0x92e0, 0xc960,   #2000
    0xd4a8, 0xd4a0, 0xda50, 0x5aa8, 0x56a0, 0xaad8, 0x25d0, 0x92d0, 0xc958, 0xa950,   #2010
    0xb4a0, 0xb550, 0xb550, 0x55a8, 0x4ba0, 0xa5b0, 0x52b8, 0x52b0, 0xa930, 0x74a8,   #2020
    0x6aa0, 0xad50, 0x4da8, 0x4b60, 0x9570, 0xa4e0, 0xd260, 0xe930, 0xd530, 0x5aa0,   #2030
    0x6b50, 0x96d0, 0x4ae8, 0x4ad0, 0xa4d0, 0xd258, 0xd250, 0xd520, 0xdaa0, 0xb5a0,   #2040
    0x56d0, 0x4ad8, 0x49b0, 0xa4b8, 0xa4b0, 0xaa50, 0xb528, 0x6d20, 0xada0, 0x55b0,   #2050
]

#数组gLanarMonth存放阴历1901年到2050年闰月的月份，如没有则为0，每字节存两年
g_lunar_month = [
    0x00, 0x50, 0x04, 0x00, 0x20,   #1910
    0x60, 0x05, 0x00, 0x20, 0x70,   #1920
    0x05, 0x00, 0x40, 0x02, 0x06,   #1930
    0x00, 0x50, 0x03, 0x07, 0x00,   #1940
    0x60, 0x04, 0x00, 0x20, 0x70,   #1950
    0x05, 0x00, 0x30, 0x80, 0x06,   #1960
    0x00, 0x40, 0x03, 0x07, 0x00,   #1970
    0x50, 0x04, 0x08, 0x00, 0x60,   #1980
    0x04, 0x0a, 0x00, 0x60, 0x05,   #1990
    0x00, 0x30, 0x80, 0x05, 0x00,   #2000
    0x40, 0x02, 0x07, 0x00, 0x50,   #2010
    0x04, 0x09, 0x00, 0x60, 0x04,   #2020
    0x00, 0x20, 0x60, 0x05, 0x00,   #2030
    0x30, 0xb0, 0x06, 0x00, 0x50,   #2040
    0x02, 0x07, 0x00, 0x50, 0x03    #2050
]

#==================================================================================

from datetime import date, datetime, timedelta
from calendar import Calendar as Cal

START_YEAR = 1901

def get_leap_month(lunar_year):
    flag = g_lunar_month[(lunar_year - START_YEAR) / 2]
    if (lunar_year - START_YEAR) % 2:
        return flag & 0x0f
    else:
        return flag >> 4

def lunar_month_days(lunar_year, lunar_month):
    if (lunar_year < START_YEAR):
        return 30

    high, low = 0, 29
    iBit = 16 - lunar_month;

    if (lunar_month > get_leap_month(lunar_year) and get_leap_month(lunar_year)):
        iBit -= 1

    if (g_lunar_month_day[lunar_year - START_YEAR] & (1 << iBit)):
        low += 1
       
    if (lunar_month == get_leap_month(lunar_year)):
        if (g_lunar_month_day[lunar_year - START_YEAR] & (1 << (iBit -1))):
             high = 30
        else:
             high = 29

    return (high, low)

def lunar_year_days(year):
    days = 0
    for i in range(1, 13):
        (high, low) = lunar_month_days(year, i)
        days += high
        days += low
    return days

def get_ludar_date(tm):
    span_days = (tm - datetime(1901, 1, 1)).days
    
    #阳历1901年2月19日为阴历1901年正月初一
    #阳历1901年1月1日到2月19日共有49天
    if (span_days <49):
        year = START_YEAR - 1
        if (span_days <19):
          month = 11; 
          day = 11 + span_days
        else:
            month = 12;
            day = span_days - 18
            print year, month, day
        return (year, month, day)

    #下面从阴历1901年正月初一算起
    span_days -= 49
    year, month, day = START_YEAR, 1, 1
    #计算年
    tmp = lunar_year_days(year)
    while span_days >= tmp:
        span_days -= tmp
        year += 1
        tmp = lunar_year_days(year)

    #计算月
    (foo, tmp) = lunar_month_days(year, month)
    while span_days >= tmp:
        span_days -= tmp
        if (month == get_leap_month(year)):
            (tmp, foo) = lunar_month_days(year, month)
            if (span_days < tmp):
                return (0, 0, 0)
            span_days -= tmp
        month += 1
        (foo, tmp) = lunar_month_days(year, month)

    #计算日
    day += span_days
#    print tm.year, tm.month, tm.day
#    print year,month,day
    return date(year, month, day)

def get_Calender_date((year,month,day)):
    #根据阴历打印公历
#    cal_y = tm_lunar.year
#    cal_m = tm_lunar.month
#    start_date = datetime(cal_y, cal_m, 1)
#    end_date = datetime(cal_y, cal_m, 1) + timedelta(90)
    year,month,day = int(year),int(month),int(day)
    flag = 0
    for i in range(90):
        cal_date = datetime(year, month, 1) + timedelta(i)
        if get_ludar_date(cal_date) == date(year, month, day):
            flag = 1
            break
    if flag == 1:
        return cal_date
    else:
        return None

#print get_ludar_date( datetime.now())
#get_ludar_date( datetime(1901,2,1))
#cal_date = get_Calender_date((2009,2,30))
#print cal_date